1. Field of Invention
The invention relates to an ink supply connection device for connecting an ink supply cartridge to a head holder which supports a recording head that ejects ink.
2. Description of Related Art
A conventional ink supply connection device (hereinafter, referred to as "connection device") is disclosed in Japanese Unexamined Patent Publication Nos. Hei 8-174959 and 8-174862 and is shown in FIGS. 4A and 4B. FIGS. 4A and 4B show a conventional ink cartridge 42, and a conventional head holder 46, to which a recording head 44 is fixed. The head holder 46 has an ink supply connection member 48. The ink cartridge 42 (hereinafter referred to as "cartridge") includes an ink supply hole 50. When the cartridge 42 is connected to the head holder 46, the connection member 48 enters the ink supply hole 50 so that ink is supplied to the recording head 44 through the connection member 48.
The head holder 46 is fixed to a carriage (not shown). By moving the carriage, the recording head 44 is moved to a desired position relative to a recording medium. The recording head 44 then ejects ink to form an image on the recording medium such as, for example, a character or a graphical illustration.
As the carriage moves, the cartridge 42 and the head holder 46 are subject to forces which cause them to vibrate. In some circumstances, vibrations of the cartridge 42 form gaps between the connection member 48 and the ink supply hole 50. Air bubbles may enter through such gaps and be drawn into the recording head 44. If this happens, ink ejection may become unstable or impossible.
To prevent this from occurring, the cartridge 42 shown in FIGS. 4A and 4B is provided with a protrusion 52 formed on a rear surface that faces the recording head 44. The head holder 46 includes a recess 54 for receiving the protrusion 52. Furthermore, the cartridge 42 has a recess 56 on its bottom surface, and the head holder 46 has an engaging portion 58 corresponding to the recess 56. Vibration of the cartridge 42 in the head holder 46 is prevented by the engagement between the protrusion 52 and the recess 54 and between the recess 56 and the engaging portion 58.
However, since these engagement portions fit together relatively loosely so that the cartridge 42 can be easily removed from the head holder 46, the engagement portions are insufficient for eliminating play or rattle therebetween. Although various other mechanisms for preventing vibrations of the ink cartridge 42 have been proposed, such mechanisms are subject to problems including, for example, an increased number of component parts as well as being a resistance or an impediment to cartridge attachment and detachment.